Researchers have identified the reason why individuals with long Covid experience prolonged periods of fatigue, illness, and discomfort after physical activity.

According to experts, there is evidence to suggest that biological factors such as severe muscle damage, mitochondrial issues, and the presence of microclots may be responsible for certain changes within the body.

Dr. Rob Wüst, one of the authors of the study at Vrije Universiteit Amsterdam, stated that this confirms that there is an issue within the body related to the disease.

It is estimated that Long Covid impacts approximately 2 million individuals in the UK, with a significant number reporting prolonged symptom aggravation following even a single episode of physical activity.

The research, which was published in the journal Nature Communications, included 25 individuals who had long-lasting symptoms of Covid after physical activity and 21 individuals who had fully recovered from the virus. None of the participants had been hospitalized due to Covid, and all were previously healthy and of working age before contracting the virus.

Every individual used an exercise bike for approximately 10-15 minutes, and samples of blood and skeletal muscle were collected one week prior to and the day following the activity.

On average, individuals with long Covid had a lower exercise capacity compared to healthy participants. Although there were differences among patients.

The scientists studied the tissue samples collected prior to physical activity and discovered that individuals with long-lasting Covid had a higher percentage of white muscle fibers compared to those who were healthy. These fibers have lower levels of mitochondria, which are responsible for producing energy, and also have fewer capillaries.

The researchers also discovered indications that the mitochondria in individuals experiencing long Covid were not functioning as efficiently as those in the control group of healthy individuals.

According to Wüst, the results help to understand why individuals with long-term Covid experience reduced exercise capabilities.

The researchers also discovered that individuals with long-term Covid had increased amounts of amyloid protein clusters in their skeletal muscles. However, there is no proof to support the theory that these “microclots” are obstructing blood flow in the same way some experts have suggested in the past.

After comparing biopsies taken before and after cycling, it was found that the function of the mitochondria declined in those with long Covid following exercise. These individuals also experienced a greater amount of tissue damage and showed indications of the body trying to repair itself.

Wüst stated that this could clarify the muscle discomfort that these patients are feeling following physical activity.

According to him, the results emphasized that individuals experiencing long-term effects of Covid should avoid strenuous physical activity.

According to him, it can harm your muscles, exacerbate your metabolism, and potentially account for the lingering muscle soreness and tiredness experienced weeks after working out.

According to Prof Betty Raman, an expert from the University of Oxford who was not part of the study, her own research indicates that issues with mitochondria could contribute to the fatigue experienced by individuals with long Covid. The recent study further supports the notion that treatments targeting mitochondrial health may be helpful.

However, Raman pointed out that there may be more to the situation: “Although it is possible that fatigue is linked to these metabolic issues, there could also be other factors at play, such as ongoing inflammation.”

Source: theguardian.com